title: Biosynthetic mechanism for L-Gulose in main polar lipids of Thermoplasma acidophilum and possible resemblance to plant ascorbic acid biosynthesis.
abstract: L-Gulose is a very rare sugar, but appears as a sugar component of the main polar lipids characteristic in such a thermophilic archaeon as Thermoplasma acidophilum that lives without cell walls in a highly acidic environment. The biosynthesis of L-gulose in this thermophilic organism was investigated with deuterium-labeling experiments. L-Gulose was found to be biosynthesized from D-glucose via stepwise stereochemical inversion at C-2 and C-5. The involvement of an epimerase related to GDP-mannose 3,5-epimerase, the key enzyme of plant ascorbate biosynthesis, was also suggested in this C-5 inversion. The resemblance of L-gulose biosynthesis in archaea and plants might be suggested from these results.
authors.affiliation: Department of Earth and Planetary Sciences, Graduate School of Sciences, Kyushu University.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Yamauchi
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Nakayama
mesh_terms: D001205:Ascorbic Acid / Q000096:biosynthesis*; D005947:Glucose / Q000378:metabolism; D006601:Hexoses / Q000096:biosynthesis* / Q000737:chemistry; D008055:Lipids / Q000737:chemistry*; D010944:Plants / Q000378:metabolism*; D013237:Stereoisomerism; D013822:Thermoplasma
chemical_list: D006601:Hexoses; D008055:Lipids; C057406:gulose; D005947:Glucose; D001205:Ascorbic Acid